The effects of vitamin E on the prevention and treatment of progressive liver disease, Ig A nephropathy (nephritis marked by inflamation of the renal capillaries). Dietary supplementation with vitamin E in a study with an Ig A rat model indicated that blood and calcium in the urine was thinned, renal blood flow was stabilized, and lipid peroxidation (high oxidation) of the renal parenchyma (essential tissue) was reduced. These findings suggest that increased vitamin E intake could modulate progressive renal injury in this disease state. The study will use children with Ig A nephropathy so as to test the effects of early treatment on this slowly progressive disease. Supplemental vitamin E will be given daily for two years to children with Ig A nephropathy in a double blind, placebo-controlled experimental design. The primary aim will be the incidence of hematuria (blood in the urine). Secondary aims will be changes in microalbuminaria (albumin in the urine), and glomerular filtration rate. Measurements of urinary erythrocytes (red blood cells) will be made before treatment and at four month intervals for the duration of the study. A dosage of 400 IU per day will be given to children weighing less than 30 kg. To children weighing more, a dosage of 2 x 400 IU per day will be given. Research material will be obtained from the patients and their medical records and it will be characterized by creatinine clearance, proteinuria, urinalysis, and index renal biopsies in addition to the routine, every fourth monthly biochemical determinations.